Vacuum Hold Down for Feeder Tray

ABSTRACT

A vacuum apparatus holds flat printed product in a feeder tray of a document feeding apparatus. The apparatus is particularly useful for feeding sheet material such as newspapers one at a time from the bottom of a stack. The apparatus uses existing vacuum connections in the document feeder and is easily mounted to existing feeder trays as part of a retrofit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority on U.S. Provisional Application Ser.No. 61/152,485 filed Feb. 13, 2009, which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an apparatus for holding down flat productssuch as newspaper inserts, sheets, signatures and the like in a feedertray. More particularly, the invention relates to a vacuum hold downapparatus for a feeder tray.

2. Description of the Related Art

In the graphic arts and newspaper industries, sheet feeding apparatusfor feeding sheet material one at a time from the bottom of a stack areoften employed to automatically feed flat printed or other products suchas newspapers. The bottom conveyance type of document feeding apparatusis conventionally used as it is excellent for paper separatingefficiency.

The bottom conveyance type of sheet feeding apparatus typically has twobasic sections that operate together in coordinated fashion. First, afeeder tray provides a horizontal support on which a vertical stack ofsheet material is loaded. Second, a feeding system located adjacent tothe feeder tray feeds the flat printed or other products such asnewspapers into other areas of the machine.

Devices for feeding sheet material from the bottom of a stack aretypically of two types, friction feeders or gripper feeders. Frictionfeeders, under normal conditions, are very reliable in feeding sheetsindividually from the bottom of a stack. However, they are particularlysusceptible to misfeeds and/or multi-feeds when subject to the harshenvironment of feeding newspaper. Gripper feeders are more reliable forfeeding sheets in harsh environmental conditions, but require precisecomplex control to assure pickup of single sheets (i.e., for preventionof misfeeds or multi-feeds).

Furthermore, vacuum suckers in a gripper feeder have a tendency toadhere to only the outer half of the jacket on voluminous newspapershaving loose collections of other sections. In some city newspapers, theoutermost jacket is simply used to receive a loose, side-by-sidecollection of other sections within itself and lacks a cooperatinginterleaving between the outer jacket and those sections there within.The tremendous weight and friction of those newspapers above the bottomone in the stack may cause the outer jacket to be feed while thecontents of the jacket stay behind, thereby failing to feed the entirenewspaper and resulting in frustrating, time consuming jam-ups of theequipment.

Conversely, if thin, single sheet articles such as inserts are attemptedto be fed at the other extreme, the vacuum can bleed through to the nextarticle above so that proper separation does not occur and more than onearticle at a time is fed. In addition, other problems such as staticcharge attraction between sheets, tacky or partially dried ink, andmisalignment of the vertical stack of sheet material can also result inmulti-feeds.

Thus, a need exists for an apparatus for holding down flat products suchas newspaper inserts, sheets, signatures and the like in a feeder trayto insure proper paper separation. For best results, the sheet hold downprocess should be able to be performed automatically orsemi-automatically.

SUMMARY OF THE INVENTION

The invention provides an apparatus for holding flat paper products in afeeder tray of a bottom conveyance type of document feeder to insurethat sheet material feeds one at a time from the bottom of the stack.The invention also provides a vacuum hold down apparatus for a feedertray that utilizes existing vacuum connections to the document feeder.The invention also provides a vacuum hold down apparatus for a feedertray that is economical to build and easily mounted on to existingfeeder trays as part of a machine upgrade or retrofit.

The invention utilizes a vacuum cross bar that is configured to mount onto preexisting feeder trays. Broadly speaking, the vacuum hold downapparatus comprises a base having a flat bottom surface for mounting thebase to the feeder tray. The base has a top surface for receiving a flatproduct which is connected at a forward edge to the bottom surface. Athird surface connects the bottom surface to the top surface at arearward edge. A channel is proximately located on the top surface ofthe base in contact with the flat product. A hollow bore is proximatelylocated in an interior portion of the base and is connected to thechannel through a plurality of vacuum ports proximately located in thechannel.

In one embodiment of the invention, the top surface has a curvilinearrecess proximately located forward of the channel. The purpose of thisrecess is to provide a cavity for the folded end of the bottom newspaperto lie while the second newspaper in the stack rests against the vacuumchannel and is restrained by the vacuum. The top surface has a forwardfacing angle to provide a slight gravity feed to the newspaper. In thisembodiment, the third surface is an arcuate surface to provideadditional clearance for the folded end of the stack of newspapers.

A longitudinal channel is centered on the angle portion of the topsurface to provide a vacuum plenum. The purpose of this plenum is tohold the second flat paper product in the stack while the bottom productis fed. A series of holes intersect the channel and run the entirelength. At the other end, the holes intersect a hollow bore that passesthrough the center of the base. The thru bore design is preferred froman ease of manufacturing perspective. One end of the bore is suppliedwith a standard threaded or press-fit fitting for insertions into thebore. The other end of the fitting is a standard threaded orquick-disconnect hose type fitting which is commonly available in theart. Standard flexible hosing is used to connect the vacuum hold downapparatus to the existing vacuum source of the machine. A throttling ormetering valve maybe installed in the vacuum line to control the levelof vacuum supplied. Automatic regulation of the vacuum is alsoconsidered within the scope of the invention. The other end of the borehas a standard threaded or press-fitted plug to seal the end of thecavity.

A counter bored hole is provided through the third surface which allowsfor the insertion of a bolt or machine screw to attach the vacuum holddown apparatus to the feeder tray. The counter bore allows the bolt orscrew head to be recessed away from the flat paper product to precludeinterference between the bolt and the flat product. A tee nut isprovided to align the apparatus in the existing slots which are commonlypart of a feeder tray. Bolt and tee nut size is variable and can easilybe matched to any slots size.

In another embodiment, the invention comprises a wedged-shaped structurehaving a bottom surface for mounting the base to a feeder tray and anangled top surface for receiving a flat product. The top surface has aforward facing angle to provide a slight gravity feed to the newspaperand is connected at a forward edge to the bottom surface. A thirdgenerally vertical surface connects the bottom surface to the topsurface at a rearward edge. A longitudinal channel proximately locatedon the top surface of the base is biased towards the rearward end of thetop surface to provide vacuum to hold the trailing edge of the flatpaper product during feeding. A hollow bore is proximately located in aninterior portion of the base and is connected to the channel through aplurality of holes forming a vacuum port. A series of counter boredholes are provided to fasten the base to the feeder tray. The series ofholes provides flexibility in mounting the base to the feeder tray andinsures that the wedge is compatible with the multiple feeder tray slotarrangements commercially available. A means for attaching the base to avacuum source is also provided.

The vacuum wedge base has a smaller longitudinally width than thecurvilinear base and is preferably used in pairs proximately spaced at adistance equal to the width of a newspaper. A center wedge support ismounted in between the two small wedge bases to support the center ofthe newspaper pile. The vacuum connection to the two bases is a parallelsource connection using standard hose as known in the art.

Those skilled in the art will further appreciate the above-mentionedadvantages of the vacuum hold down apparatus, together with otherimportant aspects thereof, upon reading the detailed description whichfollows in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the present invention may be more fullyunderstood by reference to one or more of the following drawings, inwhich:

FIG. 1 is a perspective view showing the external appearance of oneembodiment of the invention installed on a feeder tray;

FIG. 2 is a perspective, simplified view of the invention of FIG. 1showing certain internal structures;

FIG. 3 is a perspective view of the invention of FIG. 1 showing theinterface with a flat product;

FIG. 4 is a perspective view showing the external appearance of analternate embodiment of the invention; and

FIG. 5 is a perspective view showing the external appearance of analternate embodiment of the invention installed on a feeder tray.

DETAILED DESCRIPTION OF THE INVENTION

A preferred embodiment of the invention will be described, but theinvention is not limited to this embodiment.

The overall external appearance of one embodiment of a vacuum hold downapparatus 10 installed on feeder tray 12 is shown in FIG. 1. Vacuum holddown apparatus 10 comprises base 14 having flat bottom surface 16, FIG.2, for mounting base 14 to feeder tray 12. Base 14 has top surface 18for receiving flat product 20, FIG. 3. Top surface 18 is connected tobottom surface 16 at forward edge 22, FIG. 2. Third surface 24 connectsbottom surface 16 to top surface 18 at rearward edge 26. Channel 28,FIGS. 1-3, is proximately located on top surface 18 of base 14 incontact with flat product 20, FIG. 3. Hollow bore 30 is proximatelylocated in an interior portion of base 14. A plurality of vacuum ports32, FIGS. 1-3, connect channel 28 to hollow bore 30.

In this embodiment of the apparatus 10, top surface 18 has curvilinearrecess 34 proximately located forward of channel 28 as shown in FIGS.1-3. The purpose of recess 34 is to provide a cavity for the folded endof the bottom newspaper 20 to lie while the second newspaper 20 in thestack (not shown) rest against vacuum channel 28 and is restrained bythe vacuum. Top surface 18 has forward facing angle 36, FIG. 2, toprovide a slight gravity feed to newspaper 20. In this embodiment, thirdsurface 24 is an arcuate surface to provide additional clearance forfolded end of the stack (not shown) of newspapers 20.

As shown in FIG. 1, one end of base 14 is supplied with standardthreaded or press-fit fitting 40 for insertions into bore 30, FIG. 2.The other end of fitting 40 is a standard threaded or quick-disconnecthose type fitting which is commonly available in the art. Standardflexible hosing 42 is used to connect vacuum hold down base 14 toexisting vacuum source 44. A throttling or metering valve (not shown)maybe installed in the vacuum line to control the level of vacuumsupplied. The other end of base 14 has standard threaded or press-fittedplug 46 to seal the end of bore 30, FIG. 2. Counter bored hole 50 isprovided through third surface 24 for bolt or machine screw 52. Bolt ormachine screw 52 with washer 54 and tee nut 56 are used to attach thevacuum hold down apparatus 10 to feeder tray 12.

Base 14 is preferentially made of aluminum or stainless steel andfabricated using conventional machining processes, although moldedcomposite or resin processes may be used to form base 14.

In another embodiment as shown in FIG. 4, the apparatus 10 compriseswedged-shaped structure 60 having bottom surface 62 for mountingstructure 60 to feeder tray 12. Angled top surface 64 for receiving flatproduct (not shown) has forward facing angle 66 to provide a slightgravity feed to newspaper (not shown) and is connected at forward edge68 to bottom surface 62. Third generally vertical surface 70 connectsbottom surface 62 to top surface 64 at rearward edge 72. Longitudinalchannel 74 proximately located on top surface 64 of structure 60 isbiased towards rearward end 72 of top surface 64 to provide vacuum tohold the trailing edge of the flat paper product (not shown) duringfeeding. Hollow bore 76 is proximately located in an interior portion ofstructure 60 and is connected to channel 74 through holes 78 forming avacuum port. Series of counter bored slots 80 are provided to fastenstructure 60 to feeder tray 12 using bolt or machine screw 84, FIG. 5.

As shown in FIG. 5, vacuum wedge base is preferably used in pairs 90,92. Left wedge-shaped base 90 has inner vertical edge 90 a and outervertical edge 90 b. Right wedge-shaped base 92 has inner vertical edge92 a and outer vertical edge 92 b. The spacing of left base 90 withrespect to right base 92 on feeder tray 12 is such that outer verticaledge 90 b of left base 90 is spaced proximately equal to the width of anewspaper (not shown) from outer vertical edge 92 b of right base 92.Center wedge support 94 is mounted in between wedge bases 90, 92,proximately spaced equidistance from inner edge 90 a of left base 90 andinner edge 92 a of right base 92 to support the center of the newspaperpile (not shown). Bolt or machine screw 96 attaches center support 94 tofeeder tray 12. Vacuum connection 98 is a parallel source connectionusing standard hose as known in the art to supply vacuum to bases 90,92.

Although only a few embodiments of the present invention have beendescribed, the invention is, nonetheless, to be broadly construed, andis not to be limited to these embodiments, and the scope is defined bythe claims appended hereto. Those skilled in the art will recognize theabove-described features and advantages of the invention and thatvarious substitutions and modifications may be made without departingfrom the scope and spirit of the appended claims.

REFERENCE CHARACTERS

10 Vacuum Hold Down Apparatus

12 Feeder Tray

14 Base

16 Bottom Surface

18 Top Surface

20 Flat product

22 Forward Edge

24 Third Surface

26 Rearward Edge

28 Channel

30 Hollow Bore

32 Holes

34 Curvilinear Recess

36 Forward Facing Angle

40 Fitting

42 Hose

44 Vacuum Source

46 Plug

50 Hole

52 Bolt or Machine Screw

54 Washer

55 Tee Nut

60 Wedge Shaped Base

62 Bottom Surface

64 Angled Top Surface

66 Forward Facing Angle

68 Forward Edge

70 Third Vertical Surface

72 Rearward Edge

74 Channel

76 Hollow Bore

78 Holes

80 Slots

84 Bolt or Machine Screw

90 Left Base

90 a Inner Vertical Edge

90 b Outer Vertical Edge

92 Right Base

92 a Inner Vertical Edge

92 b Outer Vertical Edge

94 Center Support

96 Bolt or Machine Screw

98 Vacuum Supply Hose

1. A vacuum hold down apparatus for a feeder tray, comprising: a basehaving a bottom surface for mounting the base to the feeder tray, a topsurface for receiving a flat product and connected at a forward edge tothe bottom surface, and a third surface for connecting the bottomsurface to the top surface at a rearward edge; a channel proximatelylocated on the top surface of the base; a hollow bore proximatelylocated in an interior portion of the base; and a plurality of vacuumports proximately located in the channel and connecting the channel tothe hollow bore.
 2. The vacuum hold down apparatus of claim 1, whereinthe top surface has a curvilinear recess proximately located forward ofthe channel.
 3. The vacuum hold down apparatus of claim 1, wherein thethird surface is an arcuate surface.
 4. The vacuum hold down apparatusof claim 1, wherein the base is a wedged shaped structure.
 5. The vacuumhold down apparatus of claim 1 further comprising: a means for fasteningthe base to the feeder tray.
 6. The vacuum hold down apparatus of claim5, wherein the means for fastening the base to the feeder tray is a nutand a bolt or a nut and a machine screw.
 7. The vacuum hold downapparatus of claim 1 further comprising: a means for attaching the baseto a vacuum source.
 8. The vacuum hold down apparatus of claim 7,wherein the means for attaching the base to a vacuum source is a hose.9. An apparatus for holding flat paper products in a feeder tray,comprising at least one base having a bottom surface for mounting thebase to a feeder tray, a top surface for receiving a flat product andconnected at a forward edge to the bottom surface, and a third surfacefor connecting the bottom surface to the top surface at a rearward edge,a channel proximately located on the top surface of the base, a hollowbore proximately located in an interior portion of the base, and aplurality of vacuum ports proximately located in the channel andconnecting the channel to the hollow bore; a first fastener forfastening the base to the feeder tray; and a second fastener forattaching the base to a vacuum source.
 10. The apparatus for holdingflat paper products of claim 9, wherein the first fastener the base is anut and a bolt or a nut and a machine screw.
 11. The apparatus forholding flat paper products of claim 9, wherein the second fastener is ahose.
 12. The apparatus for holding flat paper products of claim 9further comprising: at least one left wedge shaped base having an innervertical edge and an outer vertical edge; and at least one right wedgeshaped base having an inner vertical edge and an outer vertical edge,proximately spaced from the left base on the feeder tray whereby thedistance between the outer vertical edge of the left base and the outervertical edge of the right base is proximately equal to the width of anewspaper.
 13. The apparatus for holding flat paper products of claim 12further comprising: at least one wedge shaped support positioned betweenthe left base and the right base on the feeder tray, proximately spacedequidistance from the inner edge of the left base and the inner edge ofthe right base; and a third fastener for attaching the support to thefeeder tray.
 14. A method for holding flat paper products in a feedertray, comprising the steps of: providing at least one base having abottom surface for mounting the base to a feeder tray, a top surface forreceiving a flat product and connected at a forward edge to the bottomsurface, and a third surface for connecting the bottom surface to thetop surface at a rearward edge, a channel proximately located on the topsurface of the base, a hollow bore proximately located in an interiorportion of the base, and a plurality of vacuum ports proximately locatedin the channel and connecting the channel to the hollow bore; fasteningthe base to the feeder tray; attaching the base to a vacuum source; andapplying vacuum.